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A154882
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a(n) = smallest number with at least as many divisors as (a(n-1))^2
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0
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2, 4, 12, 120, 7560, 8648640, 1927522396800, 4747472432036420486400, 128438082648984172330026178330296384000, 6184173455628205993842062057864303743050691444602955105860128640000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| a(n)=A061799(A048691(a(n-1))). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 21 2009]
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EXAMPLE
| 4^2 = 16 with 5 divisors; smallest number with at least 5 divisors is 12
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CROSSREFS
| Sequence in context: A038791 A001696 A013333 * A062000 A053040 A154734
Adjacent sequences: A154879 A154880 A154881 * A154883 A154884 A154885
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KEYWORD
| nonn
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AUTHOR
| J. Lowell (jhbubby(AT)mindspring.com), Jan 16 2009
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EXTENSIONS
| a(6)-a(10) from Donovan Johnson (donovan.johnson(AT)yahoo.com), May 09 2009
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